Citrate synthase

high-resolution terminology - matching measurements at high-resolution

Citrate synthase

Description

Condensation of oxaloacetate with acetyl-CoA yields citrate as an entry into the TCA cycle. CS is located in the mt-matrix. CS activity is frequently used as a functional marker of the amount of mitochondria (mitochondrial elementary marker, mtE) for normalization of respiratory flux.

Abbreviation: CS

Reference: MiPNet17.04 CitrateSynthase

Normalization of respiratory flux for CS as a mitochondrial marker

Communicated by Gnaiger Erich last update 2020-04-19

Respiration of living or permeabilized cells, tissue homogenate or permeabilized tissue, and isolated mitochondria can be normalized for CS activity. Then marker-specific oxygen flux, J_O₂/CS [pmol∙s^-1∙IU^-1], is a quantitative measure of respiration that reflects mitochondrial quality, independent of mitochondrial density.

Several publications in peer-reviewed journals report respiration normalized for CS activity in units which do not make sense, e.g. [pmol∙s^-1∙mL^-1∙IU^-1], such that those numerical results are pointless. Clarification is obtained by strict definitions of normalization of rates (BEC 2020.1) and dimensional analysis, summarized in MiPNet 17.04.

References

Bioblast link	Reference	Year
Gnaiger 2020 BEC MitoPathways	Gnaiger E (2020) Mitochondrial pathways and respiratory control. An introduction to OXPHOS analysis. 5^th ed. https://doi.org/10.26124/bec:2020-0002	2020
BEC 2020.1 doi10.26124bec2020-0001.v1	Gnaiger E et al ― MitoEAGLE Task Group (2020) Mitochondrial physiology. https://doi.org/10.26124/bec:2020-0001.v1	2020
MiPNet17.04 CitrateSynthase	Laboratory protocol: Citrate synthase a mitochondrial marker enzyme.	2020-04-18